Fiber optic cable device with retractable operation

ABSTRACT

A device for providing variable length fiber optic cable and storing any excess not used. Means are provided to allow for extending and retracting fiber optic cable to prevent excess slack when in use. Optical coupling units provide optical coupling of fiber optic cable within the device. Multiple devices may be connected together to provide variable length fiber optic cable in different directions.

FIELD OF THE INVENTION

[0001] The present invention relates generally to optical fiber andoptical fiber assemblies, and more particularly to a device for storingfiber optic cable that provides retractable operation to store excesscable therein.

BACKGROUND OF THE INVENTION

[0002] The use of fiber optic cable and associated components (e.g.,optical connectors) to communicate information has increaseddramatically, due in part to the increased need to transmit largeramounts of information more rapidly (e.g., real-time video). Thesehigher data speeds can be met using an optical fiber medium.Essentially, transmission of information using fiber optics is achievedusing light pulses that traverse along a glass or plastic optical wireor optical fiber. Thus, as the need for faster communication has grown,optical fiber, because of its ability to transmit more information athigher speeds, is replacing conventional copper wire for providingeveryday communication links. For example, many telephone companies areemploying optical fiber for use in their long distance lines. Further,not only is more data transmitted at higher speeds, but optical fiber isless subject to interference (e.g., electromagnetic interference),thereby reducing the need to retransmit or amplify signals.

[0003] As recognized by the inventor hereof, with the increased use offiber optic technology, and in particular fiber optic cable, specificconnectors to connect communicating devices to, for example, a walloutlet or interface will be needed. Further, different lengths of fiberoptic cable will be needed depending upon the particular applications.For example, in much the same way that it is common to connect telephonecable to a telephone jack to provide communication using a telephonewithin a home, similar types of connections will be required for fiberoptic interfaces. However, because of the extremely small diameter offiber optic cable, problems arise that are not present when usingtraditional communication wire (e.g., telephone wire). In particular,fiber optic cable has a much greater tendency to become tangled, therebyrequiring careful deployment of the cable, for example, when variablecable length is needed. Further, the likelihood of tangled cableincreases significantly as the length of cable increases, therebyrequiring time and effort to untangle the cable. Additionally, thechance of damage to exposed fiber optic cable (e.g., between a deviceand a wall connection), for example, when tangled and knotted, isincreased, due in part to a minimum bend radius, which if exceeded, willdamage (i.e., snap) the cable. It is also more difficult to cut fiberoptic cable and provide connectors on the cable than with other types ofwire (e.g., copper wire).

SUMMARY OF THE INVENTION

[0004] The inventor has perceived a need for a device that allows forthe use of fiber optic cable (e.g., connection from a fiber optic wallinterface or outlet to a device or between devices in a Storage AreaNetwork (SAN)), while minimizing the slack in the fiber optic cable toreduce the chance of the cable becoming tangled or damaged. Further, itis desirable for such a device to allow for easy adjustment of cablelength to accommodate devices connected together at different distances,and to have connectors provided therewith.

[0005] The present invention provides a device adapted for allowing useof variable length fiber optic cable. In particular, the device allowsfor extension of cable when extra length is needed, and retraction ofcable to take up any slack. Generally, a cable winding mechanism allowsfor extension and retraction of cable as needed or desired and opticalcoupling units provide for optical coupling of different cables.

[0006] Specifically, a device of the present invention for providing avariable length of fiber optic cable while minimizing excess cableincludes means for retractably winding optical fiber on at least onespool. The device may include a first spool and a second spoolconfigured for independent retractable winding. The device may furtherbe provided wherein a first optical fiber is provided for retractablewinding in connection with the first spool, and a second optical fiberis provided for retractable winding in connection with the second spool.Further, the first and second optical fibers may be optically coupled,which may be provided using an optical light pipe. Additionally, thefirst optical fiber may be provided for retractable winding inconnection with the at least one spool and the second optical fiber maybe of a fixed length. The means for retractably winding optical fibermay be spring loaded. The first and second spools may be configured inparallel arrangement or in concentric to the arrangement.

[0007] Another embodiment of the present invention provides a deviceadapted to provide fiber optic cable of variable length and includes afirst rotatable member adapted for maintaining fiber optic cabletherearound, a second rotatable member adapted for maintaining fiberoptic cable therearound, and a fiber optic connection member foroptically connecting the fiber optic cable of the first rotatable memberand the second rotatable member. The fiber connection member may includean optical pipe having an inner lens and an outer lens. Further, aspring mechanism may be provided and adapted for automatically rotatingthe first and second rotatable members to retract each of first ends ofthe fiber optic cable.

[0008] In yet another embodiment of the present invention, an adjustablelength fiber optic coupler is provided and includes a first fiber opticsection terminating in a free end having a first connector, a secondfiber optic section optically coupled to the first fiber optic sectionand terminating in a free end having a second connector, and a retractorfor selectively winding and unwinding the first and second fiber opticsections to adjust the length of the fiber optic coupler. The first andsecond fiber optic sections may be opposite ends of a single continuousfiber optic cable or may be separate fiber optic cables opticallycoupled together. Further, the retractor may include a first windingmechanism for selectively winding the first fiber optic section and asecond winding mechanism for selectively winding the second fiber opticsection independent of the first winding mechanism.

[0009] In still another embodiment of the present invention anadjustable length fiber optic coupler includes a first fiber opticsection terminating in a free end having a first connector, a secondfiber optic section optically coupled to the first fiber optic sectionand terminating in a free end, and a retractor for selectively windingand unwinding the first fiber optic section to adjust the length of thefiber optic coupler. The first and second fiber optic sections may beseparate fiber optic cables optically coupled together. The first fiberoptic section may include duplex cable and the second fiber opticsection may include simplex cable. The adjustable length fiber opticcoupler may also include a plurality of optical coupling units opticallycoupling the fiber optic sections. The optical coupling units mayinclude a lens and mirror assembly for directing light to the fiberoptic sections and may be configured in axial alignment.

[0010] Further areas of applicability of the present invention willbecome apparent from the detailed description provided hereinafter. Itshould be understood that the detailed description and specificexamples, while indicating the preferred embodiments of the invention,are intended for purposes of illustration only and are not intended tolimit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

[0012]FIG. 1 is a side cross-sectional view of a fiber optic cabledevice constructed according to the principles of the present invention;

[0013]FIG. 2 is a perspective view of a fiber optic cable device of thepresent invention;

[0014]FIG. 3 is a plan view of fiber optic cable that may be used inconnection with a fiber optic cable device of the present invention;

[0015] FIGS. 4(a)-4(d) are block diagrams showing fiber optic cabledevices of the present invention in use;

[0016] FIGS. 5(a) and 5(b) are schematic diagrams of differentconstructions of fiber optic cable devices of the present invention;

[0017]FIG. 6 is plan view of a fiber optic cable device of the presentinvention having optical coupling units therein;

[0018]FIG. 7 is a cross-sectional view of an optical coupling unit ofthe present invention taken along the line 7-7 in FIG. 6;

[0019]FIG. 8 is a cross sectional view of an optical coupling unit ofthe present invention taken along the line 8-8 in FIG. 6;

[0020]FIG. 9 is an elevation view of an optical coupling unit of thepresent invention;

[0021] FIGS. 10(a)-10(c) are simplified plan views of differentconnections for use with the present invention;

[0022]FIG. 11 is a side plan view of an optical junction of the presentinvention;

[0023]FIG. 12(a) is a side elevation view of a plurality of fiber opticcable devices of the present invention configured as a single unit;

[0024]FIG. 12(b) is a top plan view of a plurality of fiber optic cabledevices of the present invention configured as a single unit;

[0025]FIG. 12(c) is a side cross-sectional view of one of the fiberoptic cable devices of the unit of FIGS. 12(a) and 12(b);

[0026]FIG. 13 is a top perspective view of two fiber optic cable devicesof the present invention connected together;

[0027]FIG. 14 is perspective view of a braking mechanism for a fiberoptic cable device of the present invention;

[0028]FIG. 15 is a perspective view of another fiber optic cable deviceof the present invention showing a geared braking mechanism therein; and

[0029]FIG. 16 is an exploded perspective view of another fiber opticcable device of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The following description of the preferred embodiments is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses. Thus, although the present invention isdescribed in connection with using cable of a specific length and aparticular connector, it is not so limited, and different lengths ofcable with different connectors are contemplated.

[0031] The present invention provides a device that allows for use ofvariable length of fiber optic cable while minimizing excess cable(i.e., slack). Essentially, a winding mechanism, that may include one ormore rotatable components allows for manual adjustment of the fiberoptic cable length. Further, multiple winding mechanisms or devices maybe connected together as desired or needed.

[0032] In general, and as shown in FIGS. 1 and 2, a fiber optic cabledevice 20 constructed according to the principles of the presentinvention for providing fiber optic cable 22, 23 of variable lengthgenerally includes a winding mechanism 24 (e.g., a drum) within ahousing 26. The winding mechanism 24 allows for manual operation (i.e.,rotation) to extend the available length of fiber optic cable 22, 23from an access opening and retract any additional length (i.e., slack).More preferably, the winding mechanism is configured for automaticretraction (e.g., spring loaded or using an elastic band) of fiber opticcable to minimize excess length.

[0033] Referring to one embodiment as shown in FIG. 2, the windingmechanism 24 includes two rotatable members 28, 30 allowing forindependent adjustment of the length of separate fiber optic cables 22,23 extending from the housing 26. In particular, each rotatable member28, 30 is constructed to accommodate a separate length of fiber opticcable 22, 23 (e.g., 5 meters each). As shown, each rotatable member isconstructed as a generally circular spool configured in concentricarrangement for winding and unwinding the separate lengths of fiberoptic cable 22, 23. Two light paths 25, 27 are provided for transmissionof light through the fiber optic cables 22, 23 as described in moredetail herein. It should be noted that different sizes andconfigurations of rotatable members 28, 30 are possible (e.g., side byside alignment). It further should be noted that the housing 26preferably is configured to accommodate the size and shape of therotatable members 28, 30 (e.g., generally circular shape to accommodatelengths of fiber optic cable 22, 23) as shown in different exemplaryconstructions in FIGS. 5(a) and 5(b). Further, additional controlcomponents may be provided, including for example, a handle 27 forrotating the rotatable members 28, 30 as shown in FIG. 5(a).

[0034] One end 32 of each length of the fiber optic cable 22, 23 extendsfrom the housing 26 as shown in FIG. 2. Preferably, separate openings 34are provided within the housing 26 to access each of the fiber opticcables 22, 23. Each of the ends 32 of fiber optic cable 22, 23preferably include a fiber optic type connector 36 (e.g., LC, SC orother standard connector) as shown in FIG. 3. Further, the fiber opticcable 22, 23 is generally encased within a plastic housing 38 and mayinclude one or more fibers 40 (i.e., fiber channels) therein forproviding communication of optical signals via light pulses.

[0035] An optical coupling means, such as, for example, an optical lightpipe 42 as shown in FIG. 11 is provided to optically couple the firstlength of fiber optic cable 22 and the second length of fiber opticcable 23, which may be provided, for example, on the first and secondrotatable members 28, 30. In one construction, a separate holographiclens may be provided on a reflective surface for optically coupling(i.e., connecting) each of the second ends (not shown) of the fiberoptic cable 22, 23. In this construction, an inner lens and an outerlens are each provided to optically couple (i.e., connect) the fiberoptic cable 22 on each of the rotatable members 28, 30 (e.g., inner andouter spools).

[0036] In another construction of a fiber optic cable device 20′ of thepresent invention and as shown in FIGS. 6 through 9 and 12 through 16,the rotatable members are configured along a vertical axis relative toeach other. In this construction, the rotatable members 80, 82 areconfigured to provide rotation opposite to each other and allow forvariable length of fiber optic cable, which in this construction isduplex fiber optic cable 84. The rotatable member 80 may be providedwith gears (not shown) to allow for incremental adjustment of the lengthof the fiber optic cable 84. The rotatable member 82 is preferablyconstructed having an automatic rewind mechanism (e.g., spring loaded oran elastic band) to allow for automatic retraction of the fiber opticcable 84. Excess fiber optic cable 84 is preferably stored (i.e., woundaround) on the rotatable member 82. A brake mechanism as shown in FIGS.14 and 15 may also be provided to lock the rotatable member 82 andprevent retraction of the fiber optic cable 84. However, any suitablebraking device for stopping the retraction or extension of the fiberoptic cable 84 may be provided. Further, it should be noted that therotatable members 80, 82 are preferably provided as spools, bobbins orother similar devices.

[0037] In this construction, fixed length fiber optic cable, which issimplex fiber optic cable 86, is optically coupled to the duplex fiberoptic cable 84 using optical coupling units 88, 90, 92 and 94. Theoptical coupling units provide distinct optical paths for coupling theduplex fiber optic cable 84 to each of the simplex fiber optic cables86. The optical coupling units 88, 90, 92 and 94 are preferablyconstructed in a circular shape to provide the optical paths asdescribed in more detail herein It should be noted that the simplexfiber optic cable 86 may be routed to the top, bottom or side of thefiber optic cable device 20′ depending upon the particular requirements.

[0038] Preferably, optical coupling units 88, 94 are connected (e.g., bywelding or glue solvent) to the housing 26 to prevent rotation. Opticalcoupling units 90, 92 are preferably connected to the rotatable member80 to provide for rotation as a single unit. In an alternateconstruction as shown in FIG. 12(c) a separate rotatable member 80(e.g., winding mechanism) may be provided in connection with each of thecoupling units 90 and 92.

[0039] As shown in FIGS. 6 through 9, bearings 100 are preferablyprovided between rotatable members 88, 90 and rotatable members 92, 94in the grooves 96, 98, respectively, to facilitate rotation.Essentially, the fiber optic cable device 20′ integrates mechanical andoptical components (i.e., mechanical winding mechanisms and opticalcoupling units) to allow for optical coupling of fiber optic cable thatis adapted for adjustable extension and retraction. It should further benoted that multiple fiber optic cable devices 20′ may be connectedtogether, for example as a single unit 150 as shown in FIGS. 12(a) and12(b) to provide for variable length duplex fiber optic cable 84 atdifferent ends, by connecting the simplex fiber optic cables 86 ofseparate fiber optic cable devices 20′. Different exemplaryconfigurations for connecting the ends of the fiber optic cable 84 asshown in FIGS. 10(a)-10(c) provide different connection arrangementsusing multiple fiber optic cable devices 20′, as well as differentconnection arrangements of rotatable members within the fiber opticcable devices 20′. In particular, the ends of the fiber optic cable 84may be spliced together as shown in FIG. 10(a). The ends of the fiberoptic cable 84 having fiber optic type connectors 36 may be connectedusing an optical connection 87 as shown in FIG. 10(b). Separate fiberoptic cable devices 20′ may be fused together as shown in FIG. 10(c) toprovide a physical connection.

[0040] As shown in more detail in FIG. 7, rotatable member 88 isconstructed as a generally circular member and includes an opticaljunction 102 for providing an optical path through the rotatable member.It should be noted that rotatable members 90, 92, 94 are constructed andoperate in the same manner as rotatable member 88. The optical junction102 comprises a lens and mirror assembly 104 for focusing light in theX/Y direction (i.e., upward and downward, and left and right relative toFIG. 6) as shown by the arrows. As shown in more detail in FIG. 11, thelens and mirror assembly 104 is preferably constructed as a singlepolycarbonate unit, but may be constructed of any suitable material. Forexample, the mirror may be constructed of plastic, acrylic or a sprayedmetal. The optical fiber 84 extends a distance D into an opening 103 ofthe optical junction 102. In operation, the light output of the opticalfiber 84 has divergence as shown in FIG. 8 and indicated generally byreference numeral 101. The curved portion 105 of the lens and mirrorassembly 104 is configured as both a lens and a mirror to, bothcollimate the light output from the optical fiber 84 to form a straightlight beam (i.e., collimated beam) and redirect the light path into therotatable members. Essentially, a curved mirror provides internalreflection. Collimation is provided in the X axis by the lens and mirrorassembly 104 having curved portion 105, and collimation is provided inthe Z axis by the curved portion 106.

[0041] As shown in FIG. 8, light is focused in the Z direction (i.e.,axially relative to FIG. 8) with a curved portion 106, that may beconstructed of plastic and formed by injection molding or as a separateunit thereon with laser ablation. Essentially, a gap 108 is providednear the center axis 110 with the curved portion 106 to couple light toan adjacent optical coupling unit to provide a light path (e.g., whenmultiple optical coupling units are provided). Preferably, the opticalcoupling units are constructed having about the same diameter of thefiber optic cable to be used.

[0042] In operation, the lens and mirror assembly 104 and curved portion106 cause the incident angle of light to be greater than the criticalangle of light. Thus, total internal reflection of light is achieved andused to propagate light through a fiber optic cable with the fiber opticcable device 20′. With the light optically coupled between the opticalcoupling units 88, 90, 92, 94, the rotatable members 80, 82 are operableto provide variable length fiber optic cable.

[0043] Referring now specifically to FIGS. 12 through 16, using multiplefiber optic cable devices 20′, a rack mount unit 150 that includes aplurality of connected fiber optic cable devices 20′ on both the frontand back of the rack mount unit 150 may be provided (e.g., sixteen fiberoptic cable devices 20′ on each of the front and the back). In thisembodiment, a braking mechanism 154 is provided and may be releasedusing a brake release member 156 (e.g., brake release switch or lever).Further, variable lengths of optical fiber adjustment may be provided(e.g., one meter length on one side and ten meter length on the otherside).

[0044] Further, as shown in FIG. 13, the fiber optic cable devices 20′may be mounted back to back in the rack mount unit 150 with each of thefiber optic cable devices 20′ providing individual cable-lengthadjustment (e.g., cable extension and retraction on both sides) and eachhaving a brake release member 156. In operation, the brake releasemember 156 is operated (e.g., is moved up) to allow the cable to freelyextend or retract. When the brake release member 156 is not activated,the cable is not able to move (i.e., extend or retract) withoutadditional tension (e.g., pulling) of the cable.

[0045] With respect to the braking mechanism 154, and as shown morespecifically in FIG. 14, the braking mechanism 154 is preferablyspring-loaded using a plurality of springs 160 so that a user pushes thebrake release member 156 upward to release brake pads 162 to therebyrelease the fiber optic cable. An alignment slide 164 is preferablyprovided to align the fiber optic cable. Further, as shown in FIG. 15, aspring-loaded winding assembly 166 may be geared and connected to aduplex cable spool 168, such that the duplex cable spool canincrementally unwind and wind, thereby providing the variable opticalcable length. A chamfered cable guide 170 is also provided to protectthe fiber optic cable and maintain its orientation.

[0046] Thus, and as shown in FIG. 16, a fiber optic cable device 200constructed according to the principles of the present invention mayinclude a gear assembly 180 that slides over a first optical couplingunit 182 where simplex cable divides from duplex cable at a couplingjoint 184. The fiber optic cable 185 winds as a spool on a drum 186 thatis fused to gear assemblies 188 and 190, but which can freely rotatewith respect to a second optical coupling unit 192. It should be notedthat different constructions of gear assemblies 194 and 196 may beprovided depending upon the gearing requirements (e.g., amount ofincremental adjustment for each gear notch). Optical coupling of thefirst and second optical coupling units 182 and 192 is provided asdescribed herein, for example, using the optical light pipe 42 and/oroptical junction 102. Rotation of the drum 186 allows for extension orretraction of the fiber optic cable. Further, a braking mechanism 154may be provided as described herein.

[0047] In operation, and as shown in FIGS. 4(a) through 4(d), fiberoptic cable devices 20 and 20′ of the present invention allow foradjustment of fiber optic cable 22, 23 length. For example, a firstdevice 44 and a second device 46 (e.g., two devices in a SAN) may beoptically connected by fiber optic cable 22, 23 using the presentinvention, with the position of one or more of the devices (e.g., seconddevice 46) moved as indicated by the arrows shown in FIG. 4(a). Thefiber optic storage device 20 of the present invention will allow forextension or retraction of fiber optic cable 22, 23, to accommodatemovement of the devices. As another example, and as shown in FIG. 4(b),a device 48 optically connected to an outlet interface 50 using a fiberoptic cable device 20 of the present invention provides for variablelength of fiber optic cable 22, 23. The device 48 may be moved asindicated by the arrows in FIG. 4(b), with excess slack in the fiberoptic cable 22, 23 connection minimized (i.e., retracted into thehousing 26) by the present invention. As yet another example, a firstdevice 43 and a second device 45 (e.g., two devices in a SAN) may beoptically connected by fiber optic cable using the present invention,and in particular multiple fiber optic cable devices 20′ allow formovement of the devices as indicated by the arrows shown in FIG. 4(c).Further, an additional device 47 may be connected with devices 43 and 47using the multiple fiber optic cable devices 20′ rearranged accordinglyto support the connection of the device 47. It should also be noted thatthe fiber optic cable devices 20 and 20′ may be configured and connectedin other arrangements depending upon particular needs or requirements(e.g., as a single unit 150).

[0048] Thus, although a fiber optic cable device 20, 20′ of the presentinvention for use with fiber optic cable is configured in a particulararrangement with specific cable having a particular length, otherconfigurations and lengths of cable are contemplated depending upon theparticular application and connections needed or desired. For example, asingle rotatable member may be provided allowing for adjustment of onelength of fiber optic cable, with the other length fixed. Further, thesize of the housing of the present invention may be modified toaccommodate for the storage of more or less fiber optic cable.

[0049] The description of the invention is merely exemplary in natureand, thus, variations that do not depart from the gist of the inventionare intended to be within the scope of the invention. Such variationsare not to be regarded as a departure from the spirit and scope of theinvention.

What is claimed is:
 1. A device for providing a variable length of fiberoptic cable while minimizing excess cable, the device comprising: meansfor retractably winding optical fiber on at least one spool.
 2. Thedevice according to claim 1 further comprising means for attachingoptical fiber to the at least one spool.
 3. The device according toclaim 1 further comprising a first spool and a second spool.
 4. Thedevice according to claim 3 wherein the first and second spools areconfigured for independent retractable winding.
 5. The device accordingto claim 3 wherein a first optical fiber is provided for retractablewinding in connection with the first spool.
 6. The device according toclaim 5 wherein a second optical fiber is provided for retractablewinding in connection with the second spool.
 7. The device according toclaim 6 wherein the first and second optical fibers are opticallycoupled.
 8. The device according to claim 1 wherein a first opticalfiber is provided for retractable winding in connection with the atleast one spool and a second optical fiber is of a fixed length.
 9. Thedevice according to claim 1 wherein the means for retractably windingoptical fiber is spring loaded.
 10. The device according to claim 7further comprising an optical light pipe to optically couple the firstand second optical fibers.
 11. The device according to claim 10 whereinthe light pipe comprises an inner lens and an outer lens.
 12. The deviceaccording to claim 6 further comprising a fiber optic connector at eachof an exposed end of both of the first and second optical fibers. 13.The device according to claim 6 wherein the first and second spools areconfigured in parallel arrangement.
 14. The device according to claim 6wherein the first and second spools are configured in concentricarrangement with the first spool being an inner spool and the secondspool being an outer spool, each adapted for independent operation. 15.The device according to claim 11 wherein the light pipe comprises aholographic lens on a reflective surface.
 16. A device adapted toprovide fiber optic cable of variable length, the device comprising: afirst rotatable member adapted for maintaining fiber optic cabletherearound; a second rotatable member adapted for maintaining fiberoptic cable therearound; and a fiber optic connection member foroptically connecting the fiber optic cable of the first rotatable memberand the second rotatable member.
 17. The device according to claim 16further comprising a housing for enclosing the fiber optic cabletherein.
 18. The device according to claim 17 wherein the housingfurther comprises a first opening and a second opening providing accessto first ends of the fiber optic cable maintained on each of the firstand second rotatable members.
 19. The device according to claim 18further comprising a fiber optic connection member on each of the firstends.
 20. The device according to claim 16 wherein the fiber opticconnection member comprises an optical light pipe having an inner lensand an outer lens.
 21. The device according to claim 16 furthercomprising a spring mechanism adapted for automatically rotating thefirst and second rotatable members to retract each of the first ends ofthe fiber optic cable.
 22. A method of providing variable length offiber optic cable while minimizing excess length of cable, the methodcomprising: adjusting the length of a first and second fiber optic cableusing rotatable members adapted for independent operation to separatelyadjust the length of the first and second fiber optic cable.
 23. Themethod according to claim 22 further comprising optically coupling thefirst and second fiber optic cables.
 24. The method according to claim22 further comprising configuring the rotatable members for automaticretraction of fiber optic cable.
 25. An adjustable length fiber opticcoupler comprising: a first fiber optic section terminating in a freeend having a first connector; a second fiber optic section opticallycoupled to the first fiber optic section and terminating in a free endhaving a second connector; and a retractor for selectively winding andunwinding the first and second fiber optic sections to adjust the lengthof the fiber optic coupler.
 26. The adjustable length fiber opticcoupler according to claim 25 wherein the first and second fiber opticsections are opposite ends of a single continuous fiber optic cable. 27.The adjustable length fiber optic coupler according to claim 25 whereinthe first and second fiber optic sections are separate fiber opticcables optically coupled together.
 28. The adjustable length fiber opticcoupler according to claim 25 wherein the retractor comprises a firstwinding mechanism for selectively winding the first fiber optic section,and a second winding mechanism for selectively winding the second fiberoptic section independent of the first winding mechanism.
 29. Theadjustable length fiber optic coupler according to claim 28 wherein thefirst and second fiber optic sections are opposite ends of a singlecontinuous fiber optic cable.
 30. The adjustable length fiber opticcoupler according to claim 28 wherein the first and second fiber opticsections are separate fiber optic cables optically coupled together. 31.A method of coupling two optical devices, each having a connector forcoupling with a fiber optic, the method comprising selectively operatinga retractor to extend first and second optically coupled fiber opticcables, each having a connector on their free ends, to span the distancebetween the two optical devices, connecting the connector on the firstfiber optic cable to the connector on one of the devices, and connectingthe connector on the second fiber optic cable to the connector on theother of the devices.
 32. An adjustable length fiber optic couplercomprising: a first fiber optic section terminating in a free end havinga first connector; a second fiber optic section optically coupled to thefirst fiber optic section and terminating in a free end; and a retractorfor selectively winding and unwinding the first fiber optic section toadjust the length of the fiber optic coupler.
 33. The adjustable lengthfiber optic coupler according to claim 32 wherein the first and secondfiber optic sections are separate fiber optic cables optically coupledtogether.
 34. The adjustable length fiber optic coupler according toclaim 33 wherein the first fiber optic section comprises duplex cableand the second fiber optic section comprises simplex cable.
 35. Theadjustable length fiber optic coupler according to claim 34 wherein thesecond fiber optic section comprises two separate lengths of simplexcable.
 36. The adjustable length fiber optic coupler according to claim35 wherein the two separate lengths of simplex cable are fixed.
 37. Theadjustable length fiber optic coupler according to claim 32 comprising aplurality of optical coupling units optically coupling the fiber opticsections.
 38. The adjustable length fiber optic coupler according toclaim 37 wherein at least one of the optical coupling units isrotatable.
 39. The adjustable length fiber optic coupler according toclaim 37 wherein the optical coupling units comprise a lens and mirrorassembly for directing light through the fiber optic sections.
 40. Theadjustable length fiber optic coupler according to claim 37 wherein theoptical coupling units are configured in axial alignment.
 41. Theadjustable length fiber optic coupler according to claim 32 wherein theretractor comprises a first and second rotatable member.
 42. Theadjustable length fiber optic coupler according to claim 32 wherein thesecond rotatable member comprises a winding mechanism.
 43. Theadjustable length fiber optic coupler according to claim 32 wherein thefirst rotatable member is connected to at least one of the opticalcoupling units, and together are rotatable.
 44. The adjustable lengthfiber optic coupler according to claim 32 wherein the second fiber opticsection terminating in a free end includes a second connector and isadapted for connection to a second adjustable length fiber opticcoupler.